When I look that plant I see short space between the internodes in the bottom of the plant ( too much light) , and large space between the top internodes (not enough light).
Just lift the pot to see if it's heavy or not , if it's lightweight it means that you need to water until you see water from the drain ( in your 5L pots you'll probably need 1L or 2L ) , add the water gently and slowly to avoid spoiling from the cups , when you see Drain coming out stop watering , wait a few minutes to see if the water gets sucked by the media , if yes add some more water until you see some more coming out from the drain, repeat the operation until it stops sucking the water , then take out the water from the cups and check ppm's drain to see if your plant needs food or just plain water or a good flush .
